zulunation wrote: ↑Sun 2024-11-10 19:55
Hello,
After a long testing I still face a problem.
I have soldered 0ohm resistor to GPIO0 and GPIO1 pins and connected them to ground.
I guess there is some problems on my board because I am working with the highest possible clock.
How much speed you are asking? If you start with slow clock and read and print your SCI registers and then gradually increase the clock speed, how far you can get.
What is the exact problem?
Are you respecting DREQ, and SPI speed limits?
Are voltages correct?
I want to ask several questions:
1. On some schematics I see that GPIO0 and GPIO1 are connected to ground with 100k resistor.
Why 100K is used.
GPIO0 and GPIO1 selects operation mode during boot. GPIO0 high: Try external SPI boot, GPIO0 low, GPIO1 high RT MIDI
The exact value for pulling down is designer dependent. And using high value resistor, the current is smaller and the pin could be used as output and so on. Design dependent stuff.
2. I heard that after chip manufacturing it passes validation procedure.
There are small percent of the chips that are "half-working" and usually thrown away.
Is any possibility that these chips can be stolen from manufacturer and sold as new?
Thanks.
Maybe my board has this kind of a chip?
Unlikely. More likely sloppy board design job or something Pasi can tell right from the crystal ball. His VS1053 crystal ball is much better than mine.